In situ analysis of garnet inclusion in diamond using single-crystal X-ray diffraction and X-ray micro-tomography

Nestola, Fabrizio; Merli, Marcello; Nimis, Paolo; Parisatto, Matteo; Kopylova, Maya G.; Stefano, Andrea De; Longo, M.; Ziberna, Luca; Manghnani, Murli H.

doi:10.1127/0935-1221/2012/0024-2212

Cited by 20 publications

(10 citation statements)

References 30 publications

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“…These methods are based on the measurement of the "internal pressure" (hereafter P i and also called "residual" or "remnant" pressure), that is the pressure exerted by the diamond on the inclusion when the diamond-inclusion pair is at room P-T. Such pressure can be retreived by using three different techniques: (1) microRaman spectroscopy (e.g., Izraeli et al 1999;Sobolev et al 2000;Nasdala et al 2003;Barron et al 2008); (2) strain birefringence analysis (Howell et al 2010), and (3) single-crystal X-ray diffraction (Harris et al 1970;Nestola et al 2012). Combining the P i with data on the thermoelastic parameters (i.e., volume bulk modulus and its pressure and temperature derivatives, volume thermal expansion, shear modulus) of the diamond and of the inclusion allows one to calculate an "isomeke", i.e., a curve in P-T space along which the volume of the inclusion is equal to the volume of the cavity within the diamond for a fixed value of P i .…”

Section: Elastic Methods For Geobarometry Of Diamondsmentioning

confidence: 99%

Diamonds and the Geology of Mantle Carbon

Shirey

Cartigny

Frost

et al. 2013

Reviews in Mineralogy and Geochemistry

392

172

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The most recent advances in diamond science are reviewed, covering a variety of specific topics, such as diamond distribution in Earth, diamond composition, mineralogy and textures, diamond formation, isotope geochemistry of diamond, geochemistry, thermobarometry and geochronology of inclusions in diamonds, geology of mantle carbon. The comprehensive, cross-disciplinary nature of this review identifies some of the areas where important unknowns in diamond research can be addressed with future work: (1) the quantitative partitioning of elements and fractionation of isotopes during diamond growth, (2) the co-genetic (or not) relationship of diamond to its host inclusions and the age of diamonds, (3) the recognition and significance of primordial carbon, primary mantle carbon, or subducted carbon in the composition of diamond, (4) the speciation of C in diamond-forming fluids and the processes that control the oxygen fugacity of the mantle, (5) the deepest diamonds, their ultra-high pressure inclusions and the geodynamic processes occurring in convecting the mantle, (6) the experimental simulation of diamond formation from a variety of mantle fluids and melts, and (7) the nanostructural characteristics of diamond as they relate to all aspects of diamond formation

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Section: Elastic Methods For Geobarometry Of Diamondsmentioning

confidence: 99%

Diamonds and the Geology of Mantle Carbon

Shirey

Cartigny

Frost

et al. 2013

Reviews in Mineralogy and Geochemistry

392

172

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“…(11b)) has been used in the calculation. The P r can be obtained by using three different techniques: (1) microRaman spectroscopy (Nasdala et al, 2003); (2) strain birefringence analysis (Howell et al, 2010), and (3) single-crystal X-ray diffraction (Nestola et al, 2012). The formation P of the diamond host can then be determined, as long as its formation T independently estimated from some geothermometer or assumed from some typical geotherm (Barron, 2005;Xiong et al, 2016).…”

Section: Figurementioning

confidence: 99%

Compressional behavior of MgCr2O4 spinel from first-principles simulation

Zhang

Liu

Xiong

et al. 2016

Sci. China Earth Sci.

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The compressional behavior of the MgCr 2 O 4 spinel has been investigated with the CASTEP code using density functional theory and planewave pseudopotential technique. We treated the exchange-correlation interaction by both the local density approximation (LDA) and generalized gradient approximation (GGA) with the Perdew-Burker-Ernzerhof functional. Our simulation was conducted for the pressure range of 0-19 GPa. We obtained the isothermal bulk modulus (K T ) of the MgCr 2 O 4 spinel as 181.46(48) GPa (GGA; low boundary) or 216.1(11) GPa (LDA; high boundary), with its first derivative (K' T ) as 4.41(6) or 4.5(1), respectively. The oxygen parameter u is not constant but negatively correlated with P, and decreases by about 0.5-0.6% for the investigated P range. The component polyhedra have different compressibilities, increasing in the order of (O 4 ) 1

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“…Equilibrium proportions of the amphibole, clinopyroxene, plagioclase, and garnet are estimated to be 14.8, 25.5, 39.2, and 20.3 vol.% respectively. Phase densities chosen from minerals with similar composition are 3.21 g/cm 3 for amphibole (Oberti, Ungaretti, Cannillo, Hawthorne, & Memmi, 1995), 3.29 g/cm 3 for clinopyroxene (Mottana, Rossi, Kracher, & Kurat, 1979), 2.64 g/cm 3 for plagioclase (Phillipsi, Colville, & Ribbe, 1971), and 3.7 g/cm 3 for garnet (Nestola et al, 2012). Local bulk composition of the examined symplectite after omphacite was obtained using EMP analyses on thin mineral lamellae with an enlarged beam size (20 μm).…”

Section: Effective Bulk Compositionmentioning

confidence: 99%

Partial melting due to breakdown of an epidote‐group mineral during exhumation of ultrahigh‐pressure eclogite: An example from the North‐East Greenland Caledonides

Cao

Gilotti

Massonne

et al. 2018

Journal Metamorphic Geology

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In the North‐East Greenland Caledonides, P–T conditions and textures are consistent with partial melting of ultrahigh‐pressure (UHP) eclogite during exhumation. The eclogite contains a peak assemblage of garnet, omphacite, kyanite, coesite, rutile, and clinozoisite; in addition, phengite is inferred to have been present at peak conditions. An isochemical phase equilibrium diagram, along with garnet isopleths, constrains peak P–T conditions to be subsolidus at 3.4 GPa and 940°C. Zr‐in‐rutile thermometry on inclusions in garnet yields values of ~820°C at 3.4 GPa. In the eclogite, plagioclase may exhibit cuspate textures against surrounding omphacite and has low dihedral angles in plagioclase–clinopyroxene–garnet aggregates, features that are consistent with former melt–solid–solid boundaries and crystallized melt pockets. Graphic intergrowths of plagioclase and amphibole are present in the matrix. Small euhedral neoblasts of garnet against plagioclase are interpreted as formed from a peritectic reaction during partial melting. Polymineralic inclusions of albite+K‐feldspar and clinopyroxene+quartz±kyanite±plagioclase in large anhedral garnet display plagioclase cusps pointing into the host, which are interpreted as crystallized melt pockets. These textures, along with the mineral composition, suggest partial melting of the eclogite by reactions involving phengite and, to a large extent, an epidote‐group mineral. Calculated and experimentally determined phase relations from the literature reveal that partial melting occurred on the exhumation path, at pressures below the coesite to quartz transition. A calculated P–T phase diagram for a former melt‐bearing domain shows that the formation of the peritectic garnet rim occurred at 1.4 GPa and 900°C, with an assemblage of clinopyroxene, amphibole, and plagioclase equilibrated at 1.3 GPa and 720°C. Isochemical phase equilibrium modelling of a symplectite of clinopyroxene, plagioclase, and amphibole after omphacite, combined with the mineral composition, yields a P–T range at 1.0–1. 6 GPa, 680–1,000°C. The assemblage of amphibole and plagioclase is estimated to reach equilibrium at 717–732°C, calculated by amphibole–plagioclase thermometry for the former melt‐bearing domain and symplectite respectively. The results of this study demonstrate that partial melt formed in the UHP eclogite through breakdown of an epidote‐group mineral with minor involvement of phengite during exhumation from peak pressure; melt was subsequently crystallized on the cooling path.

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In situ analysis of garnet inclusion in diamond using single-crystal X-ray diffraction and X-ray micro-tomography

Cited by 20 publications

References 30 publications

Diamonds and the Geology of Mantle Carbon

Diamonds and the Geology of Mantle Carbon

Compressional behavior of MgCr2O4 spinel from first-principles simulation

Partial melting due to breakdown of an epidote‐group mineral during exhumation of ultrahigh‐pressure eclogite: An example from the North‐East Greenland Caledonides

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